<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/arch/powerpc/Kconfig, branch v6.9</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v6.9</id>
<link rel='self' href='http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v6.9'/>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/'/>
<updated>2024-03-17T02:34:00+00:00</updated>
<entry>
<title>powerpc/kdump: Split KEXEC_CORE and CRASH_DUMP dependency</title>
<updated>2024-03-17T02:34:00+00:00</updated>
<author>
<name>Hari Bathini</name>
<email>hbathini@linux.ibm.com</email>
</author>
<published>2024-02-26T10:30:10+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=5c4233cc0920cc90787aafe950b90f6c57a35b88'/>
<id>urn:sha1:5c4233cc0920cc90787aafe950b90f6c57a35b88</id>
<content type='text'>
Remove CONFIG_CRASH_DUMP dependency on CONFIG_KEXEC. CONFIG_KEXEC_CORE
was used at places where CONFIG_CRASH_DUMP or CONFIG_CRASH_RESERVE was
appropriate. Replace with appropriate #ifdefs to support CONFIG_KEXEC
and !CONFIG_CRASH_DUMP configuration option. Also, make CONFIG_FA_DUMP
dependent on CONFIG_CRASH_DUMP to avoid unmet dependencies for FA_DUMP
with !CONFIG_KEXEC_CORE configuration option.

Signed-off-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240226103010.589537-4-hbathini@linux.ibm.com

</content>
</entry>
<entry>
<title>Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2024-03-15T01:03:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-15T01:03:09+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=e5eb28f6d1afebed4bb7d740a797d0390bd3a357'/>
<id>urn:sha1:e5eb28f6d1afebed4bb7d740a797d0390bd3a357</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:

 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
   heap optimizations".

 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".

 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits. The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".

 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".

 - Ryusuke Konishi continues nilfs2 maintenance work in the series

	"nilfs2: eliminate kmap and kmap_atomic calls"
	"nilfs2: fix kernel bug at submit_bh_wbc()"

 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".

 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".

 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".

Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.

* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  nilfs2: prevent kernel bug at submit_bh_wbc()
  nilfs2: fix failure to detect DAT corruption in btree and direct mappings
  ocfs2: enable ocfs2_listxattr for special files
  ocfs2: remove SLAB_MEM_SPREAD flag usage
  assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
  buildid: use kmap_local_page()
  watchdog/core: remove sysctl handlers from public header
  nilfs2: use div64_ul() instead of do_div()
  mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
  kexec: copy only happens before uchunk goes to zero
  get_signal: don't initialize ksig-&gt;info if SIGNAL_GROUP_EXIT/group_exec_task
  get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
  get_signal: don't abuse ksig-&gt;info.si_signo and ksig-&gt;sig
  const_structs.checkpatch: add device_type
  Normalise "name (ad@dr)" MODULE_AUTHORs to "name &lt;ad@dr&gt;"
  dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
  list: leverage list_is_head() for list_entry_is_head()
  nilfs2: MAINTAINERS: drop unreachable project mirror site
  smp: make __smp_processor_id() 0-argument macro
  fat: fix uninitialized field in nostale filehandles
  ...
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2024-03-15T00:43:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-15T00:43:30+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=902861e34c401696ed9ad17a54c8790e7e8e3069'/>
<id>urn:sha1:902861e34c401696ed9ad17a54c8790e7e8e3069</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
   from hotplugged memory rather than only from main memory. Series
   "implement "memmap on memory" feature on s390".

 - More folio conversions from Matthew Wilcox in the series

	"Convert memcontrol charge moving to use folios"
	"mm: convert mm counter to take a folio"

 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes. The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".

 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.

 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools". Measured improvements are modest.

 - zswap cleanups and simplifications from Yosry Ahmed in the series
   "mm: zswap: simplify zswap_swapoff()".

 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is
   hotplugged as system memory.

 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.

 - More DAMON work from SeongJae Park in the series

	"mm/damon: make DAMON debugfs interface deprecation unignorable"
	"selftests/damon: add more tests for core functionalities and corner cases"
	"Docs/mm/damon: misc readability improvements"
	"mm/damon: let DAMOS feeds and tame/auto-tune itself"

 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving
   policy wherein we allocate memory across nodes in a weighted fashion
   rather than uniformly. This is beneficial in heterogeneous memory
   environments appearing with CXL.

 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".

 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".

 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format. Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.

 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
   targeted at arm64, this significantly speeds up fork() when the
   process has a large number of pte-mapped folios.

 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
   implements batching during munmap() and other pte teardown
   situations. The microbenchmark improvements are nice.

 - And in the series "Transparent Contiguous PTEs for User Mappings"
   Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings"). Kernel build times on arm64 improved nicely. Ryan's
   series "Address some contpte nits" provides some followup work.

 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page
   faults. He has also added a reproducer under the selftest code.

 - In the series "selftests/mm: Output cleanups for the compaction
   test", Mark Brown did what the title claims.

 - Kinsey Ho has added the series "mm/mglru: code cleanup and
   refactoring".

 - Even more zswap material from Nhat Pham. The series "fix and extend
   zswap kselftests" does as claimed.

 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
   in our handling of DAX on archiecctures which have virtually aliasing
   data caches. The arm architecture is the main beneficiary.

 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides
   dramatic improvements in worst-case mmap_lock hold times during
   certain userfaultfd operations.

 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series

	"page_owner: print stacks and their outstanding allocations"
	"page_owner: Fixup and cleanup"

 - Uladzislau Rezki has contributed some vmalloc scalability
   improvements in his series "Mitigate a vmap lock contention". It
   realizes a 12x improvement for a certain microbenchmark.

 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".

 - Some zsmalloc maintenance work from Chengming Zhou in the series

	"mm/zsmalloc: fix and optimize objects/page migration"
	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"

 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0. This a step along the path to implementaton of the merging
   of large anonymous folios. The series is named "Enable &gt;0 order folio
   memory compaction".

 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages()
   to an iterator".

 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".

 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios. The
   series is named "Split a folio to any lower order folios".

 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.

 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".

 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which
   are configured to use large numbers of hugetlb pages.

 - Matthew Wilcox's series "PageFlags cleanups" does that.

 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also. S390 is affected.

 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".

 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM
   Selftests".

 - Also, of course, many singleton patches to many things. Please see
   the individual changelogs for details.

* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
  mm/zswap: remove the memcpy if acomp is not sleepable
  crypto: introduce: acomp_is_async to expose if comp drivers might sleep
  memtest: use {READ,WRITE}_ONCE in memory scanning
  mm: prohibit the last subpage from reusing the entire large folio
  mm: recover pud_leaf() definitions in nopmd case
  selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
  selftests/mm: skip uffd hugetlb tests with insufficient hugepages
  selftests/mm: dont fail testsuite due to a lack of hugepages
  mm/huge_memory: skip invalid debugfs new_order input for folio split
  mm/huge_memory: check new folio order when split a folio
  mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
  mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
  mm: fix list corruption in put_pages_list
  mm: remove folio from deferred split list before uncharging it
  filemap: avoid unnecessary major faults in filemap_fault()
  mm,page_owner: drop unnecessary check
  mm,page_owner: check for null stack_record before bumping its refcount
  mm: swap: fix race between free_swap_and_cache() and swapoff()
  mm/treewide: align up pXd_leaf() retval across archs
  mm/treewide: drop pXd_large()
  ...
</content>
</entry>
<entry>
<title>Merge tag 'hardening-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux</title>
<updated>2024-03-12T21:49:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-12T21:49:30+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=216532e147b2fee6ee830f4a844bbc3cbb9137af'/>
<id>urn:sha1:216532e147b2fee6ee830f4a844bbc3cbb9137af</id>
<content type='text'>
Pull hardening updates from Kees Cook:
 "As is pretty normal for this tree, there are changes all over the
  place, especially for small fixes, selftest improvements, and improved
  macro usability.

  Some header changes ended up landing via this tree as they depended on
  the string header cleanups. Also, a notable set of changes is the work
  for the reintroduction of the UBSAN signed integer overflow sanitizer
  so that we can continue to make improvements on the compiler side to
  make this sanitizer a more viable future security hardening option.

  Summary:

   - string.h and related header cleanups (Tanzir Hasan, Andy
     Shevchenko)

   - VMCI memcpy() usage and struct_size() cleanups (Vasiliy Kovalev,
     Harshit Mogalapalli)

   - selftests/powerpc: Fix load_unaligned_zeropad build failure
     (Michael Ellerman)

   - hardened Kconfig fragment updates (Marco Elver, Lukas Bulwahn)

   - Handle tail call optimization better in LKDTM (Douglas Anderson)

   - Use long form types in overflow.h (Andy Shevchenko)

   - Add flags param to string_get_size() (Andy Shevchenko)

   - Add Coccinelle script for potential struct_size() use (Jacob
     Keller)

   - Fix objtool corner case under KCFI (Josh Poimboeuf)

   - Drop 13 year old backward compat CAP_SYS_ADMIN check (Jingzi Meng)

   - Add str_plural() helper (Michal Wajdeczko, Kees Cook)

   - Ignore relocations in .notes section

   - Add comments to explain how __is_constexpr() works

   - Fix m68k stack alignment expectations in stackinit Kunit test

   - Convert string selftests to KUnit

   - Add KUnit tests for fortified string functions

   - Improve reporting during fortified string warnings

   - Allow non-type arg to type_max() and type_min()

   - Allow strscpy() to be called with only 2 arguments

   - Add binary mode to leaking_addresses scanner

   - Various small cleanups to leaking_addresses scanner

   - Adding wrapping_*() arithmetic helper

   - Annotate initial signed integer wrap-around in refcount_t

   - Add explicit UBSAN section to MAINTAINERS

   - Fix UBSAN self-test warnings

   - Simplify UBSAN build via removal of CONFIG_UBSAN_SANITIZE_ALL

   - Reintroduce UBSAN's signed overflow sanitizer"

* tag 'hardening-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (51 commits)
  selftests/powerpc: Fix load_unaligned_zeropad build failure
  string: Convert helpers selftest to KUnit
  string: Convert selftest to KUnit
  sh: Fix build with CONFIG_UBSAN=y
  compiler.h: Explain how __is_constexpr() works
  overflow: Allow non-type arg to type_max() and type_min()
  VMCI: Fix possible memcpy() run-time warning in vmci_datagram_invoke_guest_handler()
  lib/string_helpers: Add flags param to string_get_size()
  x86, relocs: Ignore relocations in .notes section
  objtool: Fix UNWIND_HINT_{SAVE,RESTORE} across basic blocks
  overflow: Use POD in check_shl_overflow()
  lib: stackinit: Adjust target string to 8 bytes for m68k
  sparc: vdso: Disable UBSAN instrumentation
  kernel.h: Move lib/cmdline.c prototypes to string.h
  leaking_addresses: Provide mechanism to scan binary files
  leaking_addresses: Ignore input device status lines
  leaking_addresses: Use File::Temp for /tmp files
  MAINTAINERS: Update LEAKING_ADDRESSES details
  fortify: Improve buffer overflow reporting
  fortify: Add KUnit tests for runtime overflows
  ...
</content>
</entry>
<entry>
<title>arch: simplify architecture specific page size configuration</title>
<updated>2024-03-06T18:29:03+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2024-02-26T16:14:12+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=d3e5bab923d35f73c74f6dbbb761988d4f58f878'/>
<id>urn:sha1:d3e5bab923d35f73c74f6dbbb761988d4f58f878</id>
<content type='text'>
arc, arm64, parisc and powerpc all have their own Kconfig symbols
in place of the common CONFIG_PAGE_SIZE_4KB symbols. Change these
so the common symbols are the ones that are actually used, while
leaving the arhcitecture specific ones as the user visible
place for configuring it, to avoid breaking user configs.

Reviewed-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt; (powerpc32)
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Helge Deller &lt;deller@gmx.de&gt; # parisc
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
</entry>
<entry>
<title>ppc, crash: enforce KEXEC and KEXEC_FILE to select CRASH_DUMP</title>
<updated>2024-02-24T01:48:23+00:00</updated>
<author>
<name>Baoquan He</name>
<email>bhe@redhat.com</email>
</author>
<published>2024-01-24T05:12:48+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=086d67ef33ecd07ef58f271bb35c1efd20c5acbf'/>
<id>urn:sha1:086d67ef33ecd07ef58f271bb35c1efd20c5acbf</id>
<content type='text'>
In PowerPC, the crash dumping and kexec reboot share code in
arch_kexec_locate_mem_hole(), in which struct crash_mem is used.

Here enfoce enforce KEXEC and KEXEC_FILE to select CRASH_DUMP for now.

[bhe@redhat.com: fix allnoconfig on ppc]
  Link: https://lkml.kernel.org/r/ZbJwMyCpz4HDySoo@MiWiFi-R3L-srv
Link: https://lkml.kernel.org/r/20240124051254.67105-9-bhe@redhat.com
Signed-off-by: Baoquan He &lt;bhe@redhat.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Pingfan Liu &lt;piliu@redhat.com&gt;
Cc: Klara Modin &lt;klarasmodin@gmail.com&gt;
Cc: Michael Kelley &lt;mhklinux@outlook.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>crash: remove dependency of FA_DUMP on CRASH_DUMP</title>
<updated>2024-02-24T01:48:22+00:00</updated>
<author>
<name>Baoquan He</name>
<email>bhe@redhat.com</email>
</author>
<published>2024-01-24T05:12:43+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=2c44b67e2ef345c44095d241530c10cfdd610960'/>
<id>urn:sha1:2c44b67e2ef345c44095d241530c10cfdd610960</id>
<content type='text'>
In kdump kernel, /proc/vmcore is an elf file mapping the crashed kernel's
old memory content. Its elf header is constructed in 1st kernel and passed
to kdump kernel via elfcorehdr_addr. Config CRASH_DUMP enables the code
of 1st kernel's old memory accessing in different architectures.

Currently, config FA_DUMP has dependency on CRASH_DUMP because fadump
needs access global variable 'elfcorehdr_addr' to judge if it's in
kdump kernel within function is_kdump_kernel(). In the current
kernel/crash_dump.c, variable 'elfcorehdr_addr' is defined, and function
setup_elfcorehdr() used to parse kernel parameter to fetch the passed
value of elfcorehdr_addr. Only for accessing elfcorehdr_addr, FA_DUMP
really doesn't have to depends on CRASH_DUMP.

To remove the dependency of FA_DUMP on CRASH_DUMP to avoid confusion,
rename kernel/crash_dump.c to kernel/elfcorehdr.c, and build it when
CONFIG_VMCORE_INFO is ebabled. With this, FA_DUMP doesn't need to depend
on CRASH_DUMP.

[bhe@redhat.com: power/fadump: make FA_DUMP select CRASH_DUMP]
  Link: https://lkml.kernel.org/r/Zb8D1ASrgX0qVm9z@MiWiFi-R3L-srv
Link: https://lkml.kernel.org/r/20240124051254.67105-4-bhe@redhat.com
Signed-off-by: Baoquan He &lt;bhe@redhat.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Pingfan Liu &lt;piliu@redhat.com&gt;
Cc: Klara Modin &lt;klarasmodin@gmail.com&gt;
Cc: Michael Kelley &lt;mhklinux@outlook.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>crash: split vmcoreinfo exporting code out from crash_core.c</title>
<updated>2024-02-24T01:48:22+00:00</updated>
<author>
<name>Baoquan He</name>
<email>bhe@redhat.com</email>
</author>
<published>2024-01-24T05:12:42+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=443cbaf9e2fdbef7d7cae457434a6cb8a679441b'/>
<id>urn:sha1:443cbaf9e2fdbef7d7cae457434a6cb8a679441b</id>
<content type='text'>
Now move the relevant codes into separate files:
kernel/crash_reserve.c, include/linux/crash_reserve.h.

And add config item CRASH_RESERVE to control its enabling.

And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
&lt;linux/crash_core.h&gt; and config item dependency on CRASH_CORE
accordingly.

And also do renaming as follows:
 - arch/xxx/kernel/{crash_core.c =&gt; vmcore_info.c}
because they are only related to vmcoreinfo exporting on x86, arm64,
riscv.

And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
decide if build in crash_core.c.

[yang.lee@linux.alibaba.com: remove duplicated include in vmcore_info.c]
  Link: https://lkml.kernel.org/r/20240126005744.16561-1-yang.lee@linux.alibaba.com
Link: https://lkml.kernel.org/r/20240124051254.67105-3-bhe@redhat.com
Signed-off-by: Baoquan He &lt;bhe@redhat.com&gt;
Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Pingfan Liu &lt;piliu@redhat.com&gt;
Cc: Klara Modin &lt;klarasmodin@gmail.com&gt;
Cc: Michael Kelley &lt;mhklinux@outlook.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kexec: split crashkernel reservation code out from crash_core.c</title>
<updated>2024-02-24T01:48:21+00:00</updated>
<author>
<name>Baoquan He</name>
<email>bhe@redhat.com</email>
</author>
<published>2024-01-24T05:12:41+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=85fcde402db191b5f222ebfecda653777d7d084e'/>
<id>urn:sha1:85fcde402db191b5f222ebfecda653777d7d084e</id>
<content type='text'>
Patch series "Split crash out from kexec and clean up related config
items", v3.

Motivation:
=============
Previously, LKP reported a building error. When investigating, it can't
be resolved reasonablly with the present messy kdump config items.

 https://lore.kernel.org/oe-kbuild-all/202312182200.Ka7MzifQ-lkp@intel.com/

The kdump (crash dumping) related config items could causes confusions:

Firstly,

CRASH_CORE enables codes including
 - crashkernel reservation;
 - elfcorehdr updating;
 - vmcoreinfo exporting;
 - crash hotplug handling;

Now fadump of powerpc, kcore dynamic debugging and kdump all selects
CRASH_CORE, while fadump
 - fadump needs crashkernel parsing, vmcoreinfo exporting, and accessing
   global variable 'elfcorehdr_addr';
 - kcore only needs vmcoreinfo exporting;
 - kdump needs all of the current kernel/crash_core.c.

So only enabling PROC_CORE or FA_DUMP will enable CRASH_CORE, this
mislead people that we enable crash dumping, actual it's not.

Secondly,

It's not reasonable to allow KEXEC_CORE select CRASH_CORE.

Because KEXEC_CORE enables codes which allocate control pages, copy
kexec/kdump segments, and prepare for switching. These codes are
shared by both kexec reboot and kdump. We could want kexec reboot,
but disable kdump. In that case, CRASH_CORE should not be selected.

 --------------------
 CONFIG_CRASH_CORE=y
 CONFIG_KEXEC_CORE=y
 CONFIG_KEXEC=y
 CONFIG_KEXEC_FILE=y
 ---------------------

Thirdly,

It's not reasonable to allow CRASH_DUMP select KEXEC_CORE.

That could make KEXEC_CORE, CRASH_DUMP are enabled independently from
KEXEC or KEXEC_FILE. However, w/o KEXEC or KEXEC_FILE, the KEXEC_CORE
code built in doesn't make any sense because no kernel loading or
switching will happen to utilize the KEXEC_CORE code.
 ---------------------
 CONFIG_CRASH_CORE=y
 CONFIG_KEXEC_CORE=y
 CONFIG_CRASH_DUMP=y
 ---------------------

In this case, what is worse, on arch sh and arm, KEXEC relies on MMU,
while CRASH_DUMP can still be enabled when !MMU, then compiling error is
seen as the lkp test robot reported in above link.

 ------arch/sh/Kconfig------
 config ARCH_SUPPORTS_KEXEC
         def_bool MMU

 config ARCH_SUPPORTS_CRASH_DUMP
         def_bool BROKEN_ON_SMP
 ---------------------------

Changes:
===========
1, split out crash_reserve.c from crash_core.c;
2, split out vmcore_infoc. from crash_core.c;
3, move crash related codes in kexec_core.c into crash_core.c;
4, remove dependency of FA_DUMP on CRASH_DUMP;
5, clean up kdump related config items;
6, wrap up crash codes in crash related ifdefs on all 8 arch-es
   which support crash dumping, except of ppc;

Achievement:
===========
With above changes, I can rearrange the config item logic as below (the right
item depends on or is selected by the left item):

    PROC_KCORE -----------&gt; VMCORE_INFO

               |----------&gt; VMCORE_INFO
    FA_DUMP----|
               |----------&gt; CRASH_RESERVE

                                                    ----&gt;VMCORE_INFO
                                                   /
                                                   |----&gt;CRASH_RESERVE
    KEXEC      --|                                /|
                 |--&gt; KEXEC_CORE--&gt; CRASH_DUMP--&gt;/-|----&gt;PROC_VMCORE
    KEXEC_FILE --|                               \ |
                                                   \----&gt;CRASH_HOTPLUG


    KEXEC      --|
                 |--&gt; KEXEC_CORE (for kexec reboot only)
    KEXEC_FILE --|

Test
========
On all 8 architectures, including x86_64, arm64, s390x, sh, arm, mips,
riscv, loongarch, I did below three cases of config item setting and
building all passed. Take configs on x86_64 as exampmle here:

(1) Both CONFIG_KEXEC and KEXEC_FILE is unset, then all kexec/kdump
items are unset automatically:
# Kexec and crash features
# CONFIG_KEXEC is not set
# CONFIG_KEXEC_FILE is not set
# end of Kexec and crash features

(2) set CONFIG_KEXEC_FILE and 'make olddefconfig':
---------------
# Kexec and crash features
CONFIG_CRASH_RESERVE=y
CONFIG_VMCORE_INFO=y
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC_FILE=y
CONFIG_CRASH_DUMP=y
CONFIG_CRASH_HOTPLUG=y
CONFIG_CRASH_MAX_MEMORY_RANGES=8192
# end of Kexec and crash features
---------------

(3) unset CONFIG_CRASH_DUMP in case 2 and execute 'make olddefconfig':
------------------------
# Kexec and crash features
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC_FILE=y
# end of Kexec and crash features
------------------------

Note:
For ppc, it needs investigation to make clear how to split out crash
code in arch folder. Hope Hari and Pingfan can help have a look, see if
it's doable. Now, I make it either have both kexec and crash enabled, or
disable both of them altogether.


This patch (of 14):

Both kdump and fa_dump of ppc rely on crashkernel reservation.  Move the
relevant codes into separate files: crash_reserve.c,
include/linux/crash_reserve.h.

And also add config item CRASH_RESERVE to control its enabling of the
codes.  And update config items which has relationship with crashkernel
reservation.

And also change ifdeffery from CONFIG_CRASH_CORE to CONFIG_CRASH_RESERVE
when those scopes are only crashkernel reservation related.

And also rename arch/XXX/include/asm/{crash_core.h =&gt; crash_reserve.h} on
arm64, x86 and risc-v because those architectures' crash_core.h is only
related to crashkernel reservation.

[akpm@linux-foundation.org: s/CRASH_RESEERVE/CRASH_RESERVE/, per Klara Modin]
Link: https://lkml.kernel.org/r/20240124051254.67105-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20240124051254.67105-2-bhe@redhat.com
Signed-off-by: Baoquan He &lt;bhe@redhat.com&gt;
Acked-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Pingfan Liu &lt;piliu@redhat.com&gt;
Cc: Klara Modin &lt;klarasmodin@gmail.com&gt;
Cc: Michael Kelley &lt;mhklinux@outlook.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>powerpc: Kconfig: remove tautology in CONFIG_COMPAT</title>
<updated>2024-02-22T23:38:54+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2024-01-25T22:55:12+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=9a12e9a165b3b5f0695dc77e1c68947692d6285f'/>
<id>urn:sha1:9a12e9a165b3b5f0695dc77e1c68947692d6285f</id>
<content type='text'>
This reverts commit 6fcb574125e6 ("powerpc: Kconfig: disable
CONFIG_COMPAT for clang &lt; 12").

Now that the minimum supported version of LLVM for building the kernel has
been bumped to 13.0.1, this condition is always true, as the build will
fail during the configuration stage for older LLVM versions.  Remove it.

Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-6-f5ff9bda41c5@kernel.org
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: "Aneesh Kumar K.V (IBM)" &lt;aneesh.kumar@kernel.org&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Conor Dooley &lt;conor@kernel.org&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: "Naveen N. Rao" &lt;naveen.n.rao@linux.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Nicolas Schier &lt;nicolas@fjasle.eu&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
</feed>
